docs: def flatten_list(items, seqtypes=(list, tuple), in_place=True):
      """Flatten an irregular sequence.
  
      Works generally but may be slower than it could
      be if you can make assumptions about your list.
  
      `Source`__
  
      __ https://stackoverflow.com/a/10824086
  
      Parameters
      ----------
      items : iterable
          The irregular sequence to flatten.
      seqtypes : iterable of types (optional)
          Types to flatten. Default is (list, tuple).
      in_place : boolean (optional)
          Toggle in_place flattening. Default is True.
  
      Returns
      -------
      list
          Flattened list.
  
      Examples
      --------
      >>> l = [[[1, 2, 3], [4, 5]], 6]
      >>> wt.kit.flatten_list(l)
      [1, 2, 3, 4, 5, 6]
      """
      if not in_place:
          items = items[:]
      for i, _ in enumerate(items):
          while i < len(items) and isinstance(items[i], seqtypes):
              items[i : i + 1] = items[i]
      return items